Development of a Battery Management System with Flying Capacitor-type Multiport Converter in the Discontinuous Current Mode

Abstract

This paper proposes a multiport converter based on a flying capacitor converter topology for use in a battery management system. The proposed circuit operates in discontinuous current mode and pulse frequency modulation in order to reduce inductor volume. The circuit achieves load fluctuation compensation and maximum power point tracking of the photovoltaic (PV) system by deciding duty ratio based on load current and PV output current. According to the experimental results, an efficiency of more than 95.8% was achieved under all operation conditions. In addition, the maximum efficiency reached 98.8% at the rated load (750W). Furthermore, the inductor volume reduced by 85.5% compared to that of the conventional circuit using two inductors.